A question regarding the base material specifications for welder certification exams
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This post was last edited by KmFstyle on 2017-8-21 at 08:57. Recently, it was noticed that for pipe butt joints required for certification as welders, the method used is based on those previously employed for plate fillet welds. The examination guidelines state that passing the test using plate fillet welds applies to pipe fillet welds when the outer diameter of the pipe is 76 mm or greater; therefore, existing certification requirements do not cover pipe butt joints with diameters less than 76 mm. As a result, it is necessary to carry out some pipe butt joint tests to fill this gap. For the sake of convenience in conducting these tests, a combined welding method is used: GTAW for the root pass and SMAW for the cover pass. To ensure that manual welding can handle all pipe thicknesses, the cover layer is set at 12 mm, while the root layer is set at 3 mm based on practical needs. This means the minimum pipe thickness required is 15 mm. The problem is that for pipes with a diameter of less than 76 mm, having a thickness of at least 15 mm is quite rare. Therefore, I would like to ask everyone here: how do you handle such situations during your examinations? How to prepare test panels for exams? Everyone, please give me some advice; I’d be extremely grateful!
Were pipe butt joints covered with fillet welds made from sheet metal in the past? ? ? That’s wrong in the first place. . .
How thick can pipes smaller than 76 mm actually be used in practice? Besides, aren’t thick-walled pipes hard to find as well?
It’s true that it’s not possible to obtain them, which is why I’m turning to all of you for help. What the expert said makes sense – pipes with a thickness below 76 don’t have that much thickness either. Initially, I was concerned about ensuring that the thickness of the joints could cover everything properly; I thought that manual joining methods for pipes under 76 thickness could also handle thicker pipes above 76. But after the expert’s advice, I realized that for thicker pipes above 76, I could use plate joining to cover those joints, so there’s no need for me to worry about that thickness anymore. By the way, I’d like to ask everyone: what is the maximum thickness of pipes under 76 that you’ve seen? Stainless steel and carbon steel – let’s discuss it!
This post was last edited by wanlirn on 2017-8-21 at 11:44. For the butt jointing of small-diameter tubes, long-neck flange fittings are generally used to connect the tubes together. According to the standards, the wall thickness of tubes under size 76 is around 6 mm. For heat exchange tubes, we use those with the thickest walls, namely 38X3.5; in our company, the thickness specified is 3/18, which corresponds to 2 t = 6 mm – this thickness is sufficient for actual production purposes
Yes, that’s right; therefore, areas smaller than 76 mm cannot be covered, so we’re currently working on solving this issue
Hello, what do you mean by 3/18?
Hello, what do you mean by 3/18?
3 represents the wall thickness of the pipe, while 18 represents the outer diameter of the pipe
Thick-walled steel pipes can be made at home using round steel, and the requirements for materials in this welder’s exam are not as strict as those in the Hanjin process evaluation.
The original poster still needs to read TSG Z6002 3 times. . . . Read carefully. .